from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A small cephalopod mollusk of the genus Spirula, having a spirally coiled, partitioned internal shell.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any of the cephalopod genus Spirula
from the GNU version of the Collaborative International Dictionary of English
- n. A genus of cephalopods having a multilocular, internal, siphunculated shell in the form of a flat spiral, the coils of which are not in contact.
from The Century Dictionary and Cyclopedia
- n. In Cephalopoda: A genus of sepioid cuttlefishes, typical of the family Spirulidaæ, having a delicate shell in the hinder part of the body rolled into a flat or discoidal spiral, with discrete whorls whose involute spire presents ventrally, and no guard.
- n. A member of this genus.
- n. In sponges, an irregular spineless polyact spicule of spiral form.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a small tropical cephalopod of the genus Spirula having prominent eyes and short arms and a many-chambered shell coiled in a flat spiral
Late Latin spīrula, twisted cake, diminutive of Latin spīra, coil; see spire2.(American Heritage® Dictionary of the English Language, Fourth Edition)
Diminutive of Latin spira ("a coil") (Wiktionary)